A vessel steams 1106 miles on course 249°T...

A vessel steams 1106 miles on course 249°T...

Question 1 of 2707066636eea28f7522a1c51b7fc

A vessel steams 1106 miles on course 249°T from LAT 13°30.0'N, LONG 144°30.3'E. What is the latitude and longitude of the point of arrival by Mercator sailing?

Question 1 of 27070

Q

A vessel steams 1106 miles on course 249°T from LAT 13°30.0'N, LONG 144°30.3'E. What is the latitude and longitude of the point of arrival by Mercator sailing?

🔍 Key Concepts

• Mercator sailing formulas for difference of longitude (DLo) using course and distance • Relationship between departure, DLo, and mean latitude • How a course in the third quadrant (SW) affects latitude (north/south) and longitude (east/west)

💭 Think About

• First, determine the change of latitude (ΔLat): is the vessel moving more south than west, or more west than south on a 249°T course? • Use the Mercator sailing relationship: from course and distance, find departure, then use departure and mean latitude to find DLo. How does that affect the longitude (increasing E or approaching 180° and then W)? • Compare your computed final latitude and longitude trends (more south? more west?) against each choice to eliminate those that don’t match the direction of travel.

✅ Before You Answer

• Confirm the quadrant of the course 249°T and what that means for signs of ΔLat and DLo (N/S, E/W). • Check that your computed change of latitude from 13°30.0'N is reasonable for 1106 miles on that course (not too large or too small). • Verify whether the longitude should be significantly smaller than 144°30.3'E and in which direction (toward 0° or toward 180°) based on your DLo.